body{
    margin: 16px;
}
.avatar-preview{
    width: 100px;
    height: 100px;
    border: 1px solid silver;
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center center;
    margin-top: 4px;
}

.width100{
    width: 100px;
}
.width490{
    width: 490px;
}